‘Kakegawa S45’ originated from a hybridization made in November 1998 in Kakegawa, Japan. The female parent was a Calibrachoa breeding line with rose colored flowers known as KL1 (not patented). The male parent was Calibrachoa variety ‘Liricashower Blue’, (U.S. Plant Pat. No. 9,885).
In August 1998, F1 seed was sown from this cross and 30 plants were transplanted to outdoors. Three plants were selected for creeping and branching habit and intercrossed to produce F2 seed. In February 1999 the second generation seed was planted in the field at Kakegawa and plants with different shades of blue and red flowers were observed. Two plants were selected for deep blue flower color and creeping, branching plant habit. In August 1999 these plant lines were then vegetatively propagated and grown to flowering stage in pots. Trait stability was evaluated during the summer of 2000 in greenhouses in Japan.
The breeder selected one line, for its flower color and abundance, to be vegetatively propagated and further evaluated in Salinas, Calif. during 2001. This selection was subsequently named ‘Kakegawa S45’ and was determined to have its trait characteristics firmly fixed. ‘Kakegawa S45’ was asexually reproduced by stem cuttings in Salinas, Calif. and reproduces true to type through successive generations of asexual propagation. ‘Kakegawa S45’ is distinguished from its parental cultivars primarily in flower color.